As new styles rapidly replace the old and garments are discarded, fast fashion and clothing consumption contribute to a serious and negative environmental impact. Previous research and fast fashion’s negative sustainability consequences all imply that a change is required. Peoples’ desire “to fit in” and the resulting clothing consumption has to find its solution, and second hand consumption is suggested as a viable answer. But, to buy pre-loved garments has been considered inconvenient, time-demanding and unappealing. These attitudes towards a more sustainable consumption behavior therefore becomes a barrier to a circular fashion economy. Consequently, companies are trying to develop and offer new services that could improve the situation. One of these marketplaces are Consumer to Consumer (C2C) apps, which connect sellers and buyers of second hand items through their user accounts, meaning that the company behind the service is not involved in the transaction other than as the supplier of the software.       Previous research suggests that people's intentions towards pursuing a desired consumer behavior is positively encouraged by gamification elements. Despite this, C2C apps on the Swedish market do not use these features to promote second hand consumption. Within gamification, there are a myriad of elements and tools to choose from, where three of the most commonly used gamification elements to improve attitudes are points, badges and leaderboards, also known as the PBL triad. The Theory of Planned Behavior (TPB) states that attitude towards the behavior, together with subjective norm and perceived behavior control are the components that affect an intention to engage in a behavior, which predicts whether individuals will actually perform the behavior. Based on these considerations, this thesis identified a research gap in how gamification can affect Swedish consumers’ attitude towards using C2C apps gamified with points, badges and leaderboards. We examine how this attitude, subjective norms and perceived behavioral control, influence their intentions to use these apps. This formulates the studies research questions “ How are Swedish consumers’ attitudes towards using a C2C app affected by the gamification elements points, badges and leaderboards? and How are Swedish consumers’ intentions to use a gamified app to make wardrobe updates affected by their attitudes towards it, subjective norms and perceived behavioral control?”  To examine this issue we developed a survey to collect information about Swedish consumers’ attitudes and potential behavioral intentions to use a gamified C2C app.  The data analysis proves that all three elements in the PBL triad are able to positively affect consumer attitudes. Also, the behavioral predictions stated by the TPB were supported by all three components; consumers' expectations regarding subjective norms and behavioral control, with attitude towards the behavior being the strongest predictor.